I dont understamd this problem please help------!

1 answer:

4 0

Hello,

Let's $D_1\ the \ outflow\ of\ the\ new\ pump\\
D_2\ the \ outflow\ of\ the\ old\ pump\\\\
V \ the\ volume \of\ the\ tank\\\\

D_1*5=V==\ \textgreater \ D_1= \dfrac{V}{5} \\

D_2*7=V==\ \textgreater \ D_2= \dfrac{V}{7} \\

D_1+D_2= \dfrac{V}{5}+ \dfrac{V}{7} \\

D_1+D_2= \dfrac{7*V}{35}+ \dfrac{5*V}{35} \\

D_1+D_2= \dfrac{12V}{35} \\

Time \ for \ the \2 \pumps=V=(D_1+D_2)*\dfrac{35}{12}==>2H55min$

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Loretta grew 54 watermelons in her garden last year. This year, that number increased by 5/9. Which expression shows the number

Mars2501 [29]

Answer:

$54+\frac{5}{9}\times 54$

Step-by-step explanation:

We are given that

Loretta grew watermelons in her garden last year=54

We have to find the expression which shows the number of watermelons Loretta grew this year.

To find the expression which shows the number of watermelons Loretta grew this year by adding watermelons grew in her garden last year and number of watermelons increased .

According to question

5/9 of 54= $\frac{5}{9}\times 54$

Therefore, the expression which shows the number of watermelons Loretta grew this year

= $54+\frac{5}{9}\times 54$

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victus00 [196]

Answer:
Answer options
A. Two cities that are 7.5 cm apart on the map are actually 50 km apart.
D. Two cities that are actually 66 km apart are 9.9 cm apart on the map.
Step-by-step explanation:
Step 1
Indicate the scale as shown;
3 cm : 20 km, meaning 3 cm on the map represents 20 km on the ground
A). what does 7.5 cm represent on the ground
Distance on ground=(7.5×20)/3=50 km
B). what does 4 cm represent on the ground
Distance on ground=(4×20)/3=26.67 km
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D). what does 66 km on ground represent on the map
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shepuryov [24]

Answer:

Step-by-step explanation:

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